Of special interest, when interpreted in this way, is the legend of Prometheus. He and his brother Epimetheus are sons of the Titan Iapetus. The Titans are the offspring of the oldest generation of gods, Uranus (Heaven) and Gaea (Earth). Kronos, the youngest of the Titans, dethroned his father and seized upon the government of the world. In return, he was overpowered, with the other Titans, by his son Zeus, who became the chief of the gods. In the struggle with the Titans, Prometheus was on the side of Zeus. By his advice, Zeus banished the Titans to the nether-world. But in Prometheus there still lived the Titan spirit, he was only half a friend to Zeus. When the latter wished to exterminate men on account of their arrogance, Prometheus espoused their cause, taught them numbers, writing, and everything else which leads to culture, especially the use of fire. This aroused the wrath of Zeus against Prometheus. Hephaistos, the son of Zeus, was commissioned to make a female form of great beauty, whom the gods adorned with every possible gift. She was called Pandora, the all-gifted one. Hermes, messenger of the gods, brought her to Epimetheus, the brother of Prometheus. She brought him a casket, as a present from the gods. Epimetheus accepted the present, although Prometheus had warned him against receiving any gift from the gods. When the casket was opened, every possible human evil flew out of it. Hope alone remained, and this because Pandora quickly closed the box. Hope has therefore been left to man, as a doubtful gift of the gods. By order of Zeus, Prometheus was chained to a rock on the Caucasus, on account of his relation to man. An eagle perpetually gnaws his liver, which is as often renewed. He has to pass his life in agonising loneliness till one of the gods voluntarily sacrifices himself, _i.e._, devotes himself to death. The tormented Prometheus bears his sufferings steadfastly. It had been told him that Zeus would be dethroned by the son of a mortal unless Zeus consented to wed this mortal woman. It was important for Zeus to know this secret. He sent the messenger Hermes to Prometheus, in order to learn something about it. Prometheus refused to say anything. The legend of Heracles is connected with that of Prometheus. In the course of his wanderings Heracles comes to the Caucasus. He slays the eagle which was devouring the liver of Prometheus. The centaur Chiron, who cannot die, although suffering from an incurable wound, sacrifices himself for Prometheus, who is thereupon reconciled with the gods.